Problem: Rewrite as a simplified fraction. ${2.1\overline{4} = {?}}$
Solution: Let $x$ equal the decimal. Set up two equations such that the digits after the decimal point are identical. ${\begin{align*}100x &= 214.4444...\\ 10x &= 21.4444...\end{align*}}$ Subtracting the two equations, we have: ${90x = 193}$ ${x = \dfrac{193}{90}} \text{or} {2 \dfrac{13}{90}}$